Experimental and Theoretical Considerations
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The method used to synthesize hundreds of samples across the pseudo-ternary systems was to make combinatorial arrays of milligram-scale oxides. Throughout this section, the method used to make samples in the Li-Mn-Ni-O system will be described. The only variation needed to make samples in the Li-Co-Mn-O system is to replace the nickel starting solution with a cobalt solution (both were nitrates in these studies). This method, developed by Carey and Dahn , was closely based on that typically used for large scale samples made in a tank reactor. Carey  mixed a total of 10 μL of roughly 2 M lithium nitrate (Aldrich, 98 \(\%\)), manganese nitrate (Sigma-Aldrich, 97 \(\%\)) and nickel nitrate (Sigma-Aldrich, 97 \(\%\)) using a Cartesian Pixsys solution-processing robot shown in Fig. 2.1. Figure 2.2 (a) shows how these solutions were dispensed onto an alumina plate (Pi-Kem, 96 \(\%\)) coated with stearic acid (Aldrich, 96 \(\%\)) which served to bead the solutions. Carey then added ammonium bicarbonate (Alfa Aesar, 98 \(\%\)) in excess to cause co-precipitation of Li, Mn and Ni carbonates. After drying at 55 °C, the sample was made up of the mixed carbonate and any other products of the reaction (in Chap. 3, this will be shown to be primarily ammonium carbonate). Carey then heated the samples to 800 °C for 3 h in air to form the oxides. Silicon (100) wafers were then covered in a tacky mixture of Trilene-65 (a polymer mixture made by Lion Copolymer) and cyclohexane. The wafer was placed over the alumina plates and flipped in order to transfer the samples onto the silicon wafer. The final products were shown to be the expected spinel oxides by XRD.